The invention relates to a spinning machine having a plurality of drafting units arranged next to one another which each comprise a stripping device, and having a cleaning device for the stripping devices which can be moved along the spinning machine.
It is known from German Patent Document DE-A 38 24 986 to assign a stripping roller to the two rear pressure rollers of a drafting unit comprising three pairs of rollers, this stripping roller resting on these two rear pressure rollers. These stripping rollers of the drafting units arranged next to one another are cleaned by means of a movable cleaning device which carries a fiber waste remover with it which takes over the fiber residues adhering to the individual stripping rollers. In this case, it is also known to stop the stripping roller during the cleaning operation by means of a detent device and to detach it by means of an actuating element when the cleaning device passes by so that the stripping roller, as a result of a frictional drive, is driven by the pressure rollers to perform a rotating movement. The stripping roller is cleaned during this rotating movement. Subsequently, the stripping roller is again locked into its stripping position.
It is an object of the invention to develop a spinning machine of the initially mentioned type such that a secure and thorough cleaning of the stripping device is carried out.
This object is achieved according to preferred embodiments of the invention in that the stripping devices are arranged so that they can each be moved from an operating position into a cleaning position, and in that the cleaning device is equipped with devices for changing the stripping devices from the operating position to the cleaning position. By means of this development, it is achieved that the stripping devices which are moved into the cleaning position can be cleaned thoroughly and reliably without the danger that fiber residues or other dirt particles are pressed into the surfaces of the stripping devices by means of the pressure rollers.
In a further development of the invention, it is provided that each stripping device is provided with at least two sets of stripping elements which alternatively can be moved into the operating position and into the cleaning position. This ensures that, also during the cleaning of one stripping element, a stripping operation continues to be carried out at the respective drafting unit.
In a further development of the invention, it is provided that the continuously moving cleaning device is provided with devices which move against the adjusting elements of the stripping devices for moving the stripping device from the operating position into the cleaning position. In this case, it is utilized that the driving movement of the cleaning device is used also for moving the stripping devices from the operating position into the cleaning position so that no additional controllable drives are required.
In a further development of the invention, it is provided that the adjusting elements and/or the devices for the change operation are arranged and/or constructed in such a manner that the stripping devices of the drafting units which follow one another, with a respective opposite driving direction of the cleaning device, can be changed from the operating position into the cleaning position. A development of this type is particularly advantageous when the pressure rollers of two respective adjacent drafting units are constructed in a known manner as so-called twin pressure rollers. For reasons of space, this type of a development is particularly advantageous if the stripping devices can be swivelled out of the area of the pressure rollers.
In a further development of the invention, it is provided that the cleaning device is equipped with devices for stopping at each of the drafting units. As a result, if required, for example in the case of a yarn breakage at a spinning point pertaining to the drafting unit, an intensified cleaning of the stripping device may be carried out. In this case it is provided in addition as an advantageous further development that the cleaning device is equipped with cleaning elements which, in the stopped condition, can be applied to elements of a drafting unit. In this case, additional points which are at risk with respect to dirt deposits, such as fiber fly or the like, can then be cleaned by means of the cleaning elements.
In a further development of the invention, it is provided that the devices for changing the stripping devices from the operating position and the cleaning apparatus or cleaning apparatuses of the cleaning device are held in holding devices which can be moved away from the are of the drafting units. Thus the circumstance is taken into account that, in the case of a disturbance at a spinning point, the pertaining drafting unit may be opened. The cleaning apparatuses of the cleaning device may escape in such a manner that they drive past this opened drafting unit.
In an advantageous embodiment of the invention, it is provided that the stripping elements of the stripping devices are constructed as brush strips extending over several pressure rollers of a drafting unit which can be moved into and out of the operating position and the cleaning position around a shaft extending in the drafting direction of the drafting units. This results in a simple construction which, however, permits an intensive cleaning.
In an advantageous further development of the invention, it is also provided that the cleaning device comprises a cleaning brush which can be rotated around a shaft extending in parallel with respect to the drafting direction of the drafting units, a suction device being preferably assigned t this cleaning brush.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.